FLEX 树形菜单例子（二）

这个例子是用来选中子节点的同时展开父节点

<?xml version="1.0" encoding="utf-8"?><s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"   xmlns:s="library://ns.adobe.com/flex/spark"   xmlns:mx="library://ns.adobe.com/flex/mx"><s:layout><s:VerticalLayout horizontalAlign="center"/></s:layout><fx:Declarations><!-- 将非可视元素（例如服务、值对象）放在此处 --><fx:XML id="treeXML"><root label="监控点"><node label="厦门市软件园一期"><node label="望海路一" source="http://helpexamples.com/flash/video/cuepoints.flv"/><node label="观日路一" source="http://helpexamples.com/flash/video/cuepoints.flv"/><node label="前埔南路一" source="http://helpexamples.com/flash/video/cuepoints.flv"/><node label="虎仔山路一" source="http://helpexamples.com/flash/video/lights_long.flv"/></node><node label="厦门市软件园二期"><node label="望海路二" source="http://helpexamples.com/flash/video/cuepoints.flv"/><node label="观日路二" source="http://helpexamples.com/flash/video/cuepoints.flv"/><node label="前埔南路二" source="http://helpexamples.com/flash/video/cuepoints.flv"/><node label="虎仔山路二" source="http://helpexamples.com/flash/video/lights_long.flv"/></node><node label="厦门市软件园三期"><node label="望海路三" source="http://helpexamples.com/flash/video/cuepoints.flv"/><node label="观日路三" source="http://helpexamples.com/flash/video/cuepoints.flv"/><node label="前埔南路三" source="http://helpexamples.com/flash/video/cuepoints.flv"/><node label="虎仔山路三" source="http://helpexamples.com/flash/video/lights_long.flv"/></node></root></fx:XML></fx:Declarations><fx:Script><![CDATA[import mx.events.ListEvent;private function selectedItem():void {var label:String = textI.text;var node:XMLList = treeXML.child("node").child("node").(@label == label);expandParents(node[0]);tree.selectedItem = node[0];}private function expandParents(node:XML):void {if (node && !tree.isItemOpen(node)) {tree.expandItem(node, true);expandParents(node.parent()); }}protected function tree_itemClickHandler(event:ListEvent):void{// TODO Auto-generated method stubvar node:XML = tree.selectedItem as XML;trace(node.@label);textI.text = node.@label;}]]></fx:Script><s:TextInput text="望海路一" id="textI"/><mx:Button label="选中" click="selectedItem()"/><mx:Tree id="tree" width="300" height="400" dataProvider="{treeXML}" labelField="@label" showRoot="false"  itemClick="tree_itemClickHandler(event)"/></s:Application>